copyright © 2017, university of mohammed v rabat morocco ... · university of mohammed v rabat...

Maddah et al., JMES, 2017, 8 (6), pp. 2006-2012 2006

1. Introduction

The increase and diversities in today’s water uses lead to have high environmental impacts on groundwater and

surface water. There is a growing demand to improve current water treatment technologies for different

impurities from various water resources [1-3]. Industrial water contains heavy metals, toxic organics such as

phenol compounds and other dissolved solids that may contaminate groundwater reservoirs if not treated

beforehand [4]. Heavy metals and dissolved solids are considered as important indicators to evaluate water

quality particularly in fresh water streams such as seawater, rivers and groundwater. The presence of either

heavy metals or dissolved solids in fresh water is an indication that we have diverse water contaminants [5-7].

Membranes can separate contaminants from groundwater by passing clean water through tubular polymer films

while preventing impurities on the other side. Membrane filtrations are utilized in desalination applications for

the production of potable water because of their lower capital costs compared to other industrial treatment

processes [8]. There are four categories for membrane processes which include pressure-driven, solute-transfer,

thermal and hybrid processes as shown in Table 1 [9]. Since a membrane is a thin layer of semi-permeable

material, it can separate substances by applying a driving force across the membrane. The aim of membrane

filtration processes is to reject pollutants such as salt, microorganisms, particulates, and organics from water

[10].

There are four membrane filtration types which include microfiltration (MF), ultrafiltration (UF), nanofiltration

(NF) and reverse osmosis (RO). MF membranes separate large suspended or colloidal particles from dissolved

JMES, 2017 Volume 8, Issue 6, Page 2006-2012

http://www.jmaterenvironsci.com /

Journal of Materials and Environmental Sciences ISSN : 2028-2508

Copyright © 2017,

University of Mohammed V

Rabat Morocco

Determination of the Treatment Efficiency of Different Commercial Membrane

Modules for the Treatment of Groundwater

Hisham A. Maddah1,2

, Abdulazez S. Alzhrani1, Ahmed M. Almalki

1, M. Bassyouni

1,3,

M. H. Abdel-Aziz1,4

, Mohamed Zoromba1,5

, Mohammed A. Shihon6

1Department of Chemical Engineering, King Abdulaziz University, Rabigh, Saudi Arabia

2Department of Chemical Engineering, University of Southern California, Los Angeles, United States

3Department of Chemical Engineering, Higher Technological Institute, Tenth of Ramadan City, Egypt

4Chemical Engineering Department, Alexandria University, Alexandria, Egypt

5Department of Chemistry, Faculty of Science, Port Said University, Port Said, Egypt

6Department of Chemical Engineering, King Abdulaziz University, Jeddah, Saudi Arabia

Abstract

The goal of this study was to identify the treatment efficiency of various membrane

modules in the treatment of Yanbu Groundwater. The membrane treatment efficiency was

calculated from the removal percentages of groundwater conductivities, associated with

TDS, of the groundwater at Yanbu city. The experiment work involved four commercial

membranes and they were Polyvinylidene difluoride (FP100), Polyethersulphone

(ES404), Polyamide low-pressure film (AFC40) and Polyamide high-pressure film

(AFC99). Different pressure values were applied on each membrane type to see the effect

of the pressure on the treatment efficiency and thereby selecting the optimal operating

pressure for the treatment of the groundwater. The ideal membrane for the treatment was

selected based on a comparison between the four membranes. The optimal operating

pressures for the first three membranes FP100, ES404 and AFC40 were 10, 30 and 60,

respectively. However, the optimal operating pressure for AFC99 membrane was 61.8 bar

which was not similar to the maximum operating pressure reported in the manuals that

was 64 bar. Results showed that applying higher pressures would increase the treatment

efficiency except for the last membrane type AFC99. It was found that the best membrane

module for the treatment of the groundwater at Yanbu city would be AFC40 with a

potential to reduce fouling (prefiltration) in advanced water treatment plants with 7%

treatment efficiency.

Received 18 Jan 2017,

Revised 13 Mar 2017,

Accepted 19 Mar 2017

Keywords

Groundwater;

Membrane;

Filtration;

Salinity;

Desalination;

TDS;

Water Treatment

[email protected] , Phone: (+1) 5203697386

Journal of Materials and Environmental Sciences ISSN : 2028-2508

Copyright © 2017,

University of Mohammed 1er

Oujda Morocco

http://en.wikipedia.org/wiki/Water_quality



http://en.wikipedia.org/wiki/Stream

http://www.jmaterenvironsci.com/

mailto:[email protected]


solids at moderate pressure. UF membranes are able to eliminate medium to high molecular weight components.

However, NF membranes are designed for specific separations of low molecular weight compounds. NF

membranes require more energy due to the application of higher pressures than MF or UF because of the small

pores size. The most advanced membranes are RO membranes that are operated at high operating pressures with

an effective removal of nearly all inorganic pollutants from water. [10-16]. Table 2 shows common applications

and ideal separation processes of the different membrane types [14]. The range of nominal membrane pore sizes

for the different membranes is shown in Table 3 and Figure 1 [10-16]. It can be found that as the pore size

decreases, the operating pressure increases; and this is due to having less free volume for water to go

through. There are numerous materials for the construction of MF and UF membranes including the following: cellulose

acetate, polyvinylidene fluoride, polyacrylonitrile, polypropylene, polysulfone, polyethersulfone, or other

polymers. Each membrane has its own characteristics and properties which vary based on the used material [10].

Table 1: Various membrane processes for water treatment [9]

Membrane process Mechanism for Contaminants Removal Examples

Pressure-driven Pore size MF, UF, NF, RO

Solute-transfer Electrochemistry or diffusion ED, D*

Thermal Phase change MD, PV*

Hybrid Pretreatment, adsorption, ion exchange or coagulation -

*ED: Electrodialysis; D: Water diffusivity; MD: Membrane distillation; PV: Photovoltaic

Table 2: Various membrane separation processes and their applications [9]

Membrane Type Ideal Separation Processes Common Applications

Microfiltration (MF) Pretreatment Filtration

Ultrafiltration (UF) Proteins, carbohydrates and enzymes Whey protein concentration

Nanofiltration (NF) Minerals and salts Desalination

Reverse Osmosis (RO) Clean-up of waste effluents Purification of process water

Table 3: Typical pore size and operating pressure of various membrane types [11-16]

Membrane Type Pore Size (microns) Operating Pressure (bar)

Microfiltration (MF) 0.1-10 (1-1000 nm) 1-6.2

Ultrafiltration (UF) 0.01-0.1 (1-100 nm) 1-10

Nanofiltration (NF) < 0.001 (< 1 nm) 20-40

Reverse Osmosis (RO) < 0.001 (< 1 nm) 30-100

Figure 1: Typical pore diameter of different membranes [17]

However, cellulose acetate or ployamide materials are utilized to design NF and RO membranes. Cellulose

membranes are operated within a narrow pH range of 4 to 8 to avoid membrane biodegradation [10]. There are

wide range of membrane system configurations which includes a number of both polymeric and inorganic

membranes. The polymeric membrane types are spiral, tubular and hollow fiber membrane while the inorganic

membrane types involve ceramic and stainless steel membrane. The advantages and the ideal applications of

each membrane configuration are described and listed in Table 4 [14].


Table 4: Major advantages and ideal applications of various membrane system configurations [14]

Membrane Configuration Advantages Ideal Applications

Spiral (Polymeric) Cost-effective High volume applications with no

suspended solids

Tubular (Polymeric) Highly resistant to

plugging

Large amounts of suspended solids or

fibrous compounds

Hollow fiber (Polymeric) Possibility of backwashing Low solids liquid streams

Ceramic (Inorganic) function at extreme pH

and temperature conditions

Value added applications such as

fractionation of proteins in milk

Stainless Steel (Inorganic)

Work at elevated

particulate solids or

viscosity

Demanding applications with aggressive

process conditions or feed streams

2. Methodology and Experiment Water samples from the ground water at Yanbu city are taken with a concentration of 35.7 milli-Siemens (mS).

Four commercial membranes, as shown in Table 5, have been utilized to determine the ideal membrane type for

the treatment. Different pressure values are applied on the four membranes as tabulated in Table 6 to find out

the optimal operating pressure for the treatment. Figure 2 shows the membrane filtration test unit (Model: TR

14) that was used in the experiments. The exact technique for performing the experiment work is elucidated

from the procedure and desired operating conditions of each membrane type in Table 7 as well as the membrane

filtration test unit process flow diagram in Figure 3 [18, 19].

Table 5: Characteristics and information for the four commercial membrane types [18-22]

# Type of

Membrane

Material Max. pH

Range

Max. Pressure

(bar)

Applicable

Module

1 FP100 Polyvinylidene

difluoride (PVDF)

1.5-12 10 UF

2 ES404 Polyethersulphone 1.5-12 30 NF

3 AFC40 Polyamide low-

pressure film

1.5-9.5 60 RO

4 AFC99 Polyamide high-

pressure Film

1.5-12 64 RO

Table 6: Different applied pressure values for the four commercial membrane types

# Type of

Membrane

Applied Pressure Values (bar)

P1 P2 P3 P4

1 FP100 4 6 8 10

2 ES404 10 20 25 30

3 AFC40 30 40 50 60

4 AFC99 61 62 63 64

Table 7: Procedure and desired operating conditions for the four commercial membrane types [18-22]

# Type of

Membrane Open Valves

Sampling

Valves

Retentate

Control Valve

Membrane Maximum

Inlet Pressure (bar)

1 FP100 V2, V6, V7,

V11 and V15 Sampling 1 V15 10

2 ES404 V2, V6, V8,


3 AFC40 V2, V6, V9,


4 AFC99 V2, V6, V10,



Figure 2: The membrane filtration test unit; Model: TR 14

In each experiment, the feed tank (Tank 1) was filled up alternatingly with 15 liters of Yanbu Groundwater. The

water fed at room temperature (25°C) and the level of water was fixed with a level controller. Temperature

transmitters, pressure indicators and flow transmitters were used to ensure the system operating conditions.

Open and closed valves of the membrane filtration test unit are demonstrated in Table 7. The pump was

operated to apply different pressure set points on each membrane, as shown in Table 6. A pressure gauge was

used to control the pressure increase. The system was operated for a short time (1-4 minutes) to take the

required samples in order to determine the conductivity. Results of the four membranes were compared for the

determination of the ideal membrane for the treatment.

Equation (1) is used to calculate the exact removal percentage (treatment efficiency) of each membrane from the

initial and final samples concentrations [20].

ℝ =𝐶𝑖 − 𝐶𝑜

𝐶𝑖× 100 (1)

Where; ℝ = Groundwater membrane removal percentage, %

𝐶𝑖 = Groundwater inlet conductivity, feed, mS

𝐶𝑜 = Groundwater outlet conductivity, product, mS

Figure 3: Process flow diagram of the membrane filtration test unit; Model: TR 14; reported numbers

below TT, PI, FT and LSL are just the serial number of that unit [18, 19]


3. Results and Discussion

Results showed that the optimal operating pressures for the three membranes FP100, ES404 and AFC40 were

similar to the maximum operating pressures which were 10, 30, 60 bar, respectively. However, the optimal

operating pressure for AFC99 membrane was 61.8 bar which was not the similar to the maximum operating

pressure that was 64 bar. It was found that AFC40 would be the optimal membrane choice among the other

commercial membranes for the treatment of Yanbu Groundwater with a treatment efficiency of 7%.

Figures 4 to 7 show the effect of the applied pressure of the various commercial membranes FP100, ES404,

AFC40 and AFC99 on the groundwater conductivity (TDS concentration) at Yanbu. In Figure 4, it can be found

that when the applied pressure increased on the FP100 membrane, the conductivity increased and then decreased

sharply; this could be associated with the accumulated impurities on the membrane surface from the first sample

that were washed out with the second sample and could not be removed unless there was a high pressure

applied. ES404 membrane in Figure 5 shows fluctuation in the conductivity where the peak conductivity value

was determined to be at the beginning as expected because of the low applied pressure which might drive more

impurities with the passing water. An increase in the conductivity occurred with the third sample due to particles

accumulation on the membrane surface.

The ideal and optimum results were reserved for the AFC40 membrane in Figure 6 where we had a smooth and

linear decrease in the conductivity as we increased the applied pressure since water was forced to go through

pores faster leaving more contaminants behind. Particles accumulation observation was the reason of the

Figure 4: Effect of different applied pressures

on the treatment of the Yanbu Groundwater in

membrane #1 (FP100)



membrane #2 (ES404)



membrane #3 (AFC40)



membrane #4 (AFC99)


fluctuation in water conductivity in the AFC99 membrane as shown in Figure 7. The overall treatment

efficiency of the four commercial membranes for Yanbu Groundwater is shown in Figure 8. The treatment

efficiency of AFC40 membrane was around 7% which may reduce fouling potential and enhance diffusion [23,

24]. The experimental analysis concluded that there is an inverse correlation between the applied pressure and

the water conductivity.

Conductivities of the final water product for each of the four commercial membranes has been measured and

reported in Table 8. To simplify our calculations, the applied pressure that is related to the previous conductivity

results was determined by taking the average pressure values. A more accurate results has been found for the

relation between water conductivity and the applied pressure on the membrane from the overall study.

Obviously, we have the same previous results in which high-pressure values reduce TDS or water conductivity

of the groundwater at Yanbu.

Figure 8: The overall treatment efficiency of the four commercial membranes for Yanbu Groundwater

Table 8: Characteristics of the water product for the four commercial membranes at their averaged pressures

# Type of Membrane Average Pressure (bar) Sample Concentration (mS)

1 FP100 7 34.2

2 ES404 21.25 32.2

3 AFC40 45 32

4 AFC99 62.5 32.6

Conclusions

The four commercial membranes (FP100, ES404, AFC40 and AFC99) have been investigated in terms of their

treatment efficiency of the groundwater at Yanbu under different applied pressures. The groundwater feed

samples had a conductivity of 35.7 mS. The aim of this study was to determine the ideal membrane type for the

treatment of Yanbu Groundwater among the four commercial membranes.

Results showed that the optimal operating pressures for the three membranes FP100, ES404, AFC40 were 10,

30, 60 bar, respectively. However, the optimal operating pressure for AFC99 membrane was 61.8 bar. It is

proposed that higher pressure values would increase the removal efficiency due to the reduction in conductivity.

Our findings recommend that AFC40 is the optimum membrane choice among the other membranes for the

treatment of Yanbu Groundwater. The treatment efficiency of AFC40 membrane was approximately 7% which

may play a key role in reducing fouling issues in advance water treatment units. However, the calculated overall

treatment efficiency for the final groundwater product of the other commercial membranes FP100, ES404,

AFC99 were 2.8%, 6.5% and 5.7%, respectively.


References

1. Gutub S. A., Bassyouni M., Abdel-hamid S. M. S., Life Sci. J. 10 (2013) 464.

2. Abdel-Aziz M. H., Gutub S., Soliman M. F., Bassyouni M., Rocznik Ochrona Środowiska 18 (2016) 28.

3. Abdel-Aziz M. H., Bassyouni M., Soliman M. F., Gutub S., Magram S.F., J. Mat. Environ. Sci. 8 (2017)

1737.

4. Maddah H. A., ARPN J. of Eng. Applied Sci. 11 (2016) 1799.

5. Abdel-Aziz M. H., El-Ashtoukhy E-S. Z., Bassyouni M., Metall. and Mat. Trans. B, 47 (2016) 657.

6. Zoromba M. Sh., Ismail M.I.M., Bassyouni M., Abdel-Aziz M. H., Salah N., Memic A., Alshehry A., Coll.

Surf. A: Physicochem. Eng. Aspects 520 (2017) 121.

7. Abdel-Aziz M. H., Bassyouni M., Mansour I. A. S., Nagi A., J. Ind. Eng. Chem. 20 (2014) 2650.

8. Brief T., Tech Brief Twelve (1999).

9. Fane A. G., Desalination 106 (1996) 1.

10. Filtration M., National Drinking Water ClearingHouse (1999).

11. Wagner J., Osmonics. Inc. (2001).

12. EPA N., EPA 815-R-06-009, Office of Water (2005).

13. Maddah H. A., Chogle A. M., Membrane Water Treatment 6 (2015) 477.

14. GEA Process Engineering Inc., Membrane Filtration (2012).

15. Emis: energie- en milieu-informatiesysteem voor het Vlaamse Gewest, Microfiltration (2010).

16. Smart Membrane Solutions, Membrane Classifications (2002).

17. Sagle A., Freeman B., Biennial Report on Seawater Desal. 2 (2004) 137.

18. SOLTEQ Company, Exp. Manual Membrane Test Unit TR14 (2008).

19. ITT PCI Membranes Ltd., TP78_25 Membranes and Modules (2011).

20. Perry R. H., Green, D. W., Perry's Chemical Eng. Handbook: McGraw-Hill (1999).

21. McCabe W. L., Smith J. C., Harriott P., McGraw-Hill 5 (1993) 154.

22. Geankoplis C., Prentice Hall Press (2003).

23. Maddah H., Chogle A., Applied Water Science (2016) 1.

24. Maddah H. A., Journal of Material Science and Chemical Engineering 4 (2016) 20.

(2017) ; http://www.jmaterenvironsci.com

http://www.jmaterenvironsci.com/

copyright © 2017, university of mohammed v rabat morocco ... · university of mohammed v rabat...

Documents